The predecessor clutch actuator mechanism of U.S. Pat. No. 4,328,883, entitled "Hydraulic Actuator Mechanism for a Friction Clutch" and issued May 11, 1982, in the name of the inventor of the invention herein disclosed and claimed, provides some of the background for the preferred embodiment of this invention. That disclosure provided an earlier designed hydraulic pressure operated mechanism disposed between the master cylinder manual clutch operator and the clutch throw out bearing. Other related patents are included in the patent references made of record in the above-noted U.S. patent. The disclosure of this patent is described in detail in the above-identified co-pending patent application, and therefore is not repeated here.
U.S. Pat. No. 5,003,780, entitled, "Fluidic Valve Mechanism" and issued to the inventor of the invention herein disclosed and claimed on Apr. 2, 1991, provides additional background for the invention. That patent discloses and claims a fluid flow sensitive valve mechanism positioned in a valve chamber between first and second inlet-outlet ports. The valve mechanism controls the opening and closing of a third inlet-outlet port in response to the flow of fluid to and from the valve chamber through two or more of the ports. That patent also discloses and claims a master cylinder for a brake system with the valve mechanism being a part of the master cylinder, a generic push-pull hydraulic cable arrangement using the valve mechanism, and a vehicle parking brake system where the valve mechanism is in a hydraulic substitute for the Bowden wire type of parking brake cable. The valve mechanism of U.S. Pat. No. 5,003,780 is preferably employed in the actuating system of the invention herein disclosed and claimed, and also is preferably employed in conjunction with the reservoirs and the master cylinders using the reservoirs also herein disclosed and claimed.